Cutter-head journal assembly



Jan. 4 1927.

O. W. WEBB CUTTER HEAD JOURNAL ASSEMBLY Filed Nov. 6, 1924 2 Sheets-Sheet 1 5 Orra W1 Webb C. 1; I Gum- 0 Jan. 4 27- 1,612,998 0. W. WEBB CUTTER HEAD JOURNAL ASSEMBLY F'ile d Nov. 6. 1924. ZShoets-Sheet- 2 mo a ings at each end Patented Jan. 4, 1927.

outrun starts PATENT orr cn.

OBRA VJ. WEBB, 0F SEAZITLE, WASHINGTON, ASSIGNOB '20 S'IETSON-BOSS MACHINE COMPANY, OF SEATTLE, "WASHINGTON, A. COBYOBATIOH OF WASHINGTON.

CUTTER-HEAD JOURNAL ASSEMBLY.

Application filed November My invention relates to wood finishing machines and more particularly to planer cutter heads and supporting and drive means therefor.

In its broad aspect my invention relates to cutter-heads and shafts therefor, generally horizontal, or otherwise positioned or operating under conditions tending to bend the shaft or to cause it to vibrate, and with the cutter head positioned between the ends of the shaft, and to the means whereby the cutter head and shaft may be properly supported in bearings to resist the tendency to bending and to vibration, however caused, and whereby the shaft is free to rotate without cramping its bearings, and the cutter head is firmly held in position while rotating.

In its more specific aspect, myinvention relates to means whereby a planer cutterhead, supported intermediate the ends of a horizontal shaft, may be driven by two motors, one ateach end of the shaft, and to the means whereby a pair of antifriction bearof the shaft, outward of the cutter head, may be alined andmaintained in alinement, to hold the cutter-head firmly, to prevent vibration in the cutter-head and its shaft, and to properly support the motor rotors, notwithstanding the tendency of the shaft to bend and cramp its bearings.

it is, therefore, one of the principal objects of my invention to provide means whereby such a cutter head shaft and its four or more bearings may be maintained in perfect axial alinement, so that each bearing may properly perform its function.

Another important object is to produce a construction wherein the motors and the tool to be operated thereby may be mounted upon the same shaft to form a unitary structure, which structure is in turn held in rigid alinement for operation and for adjustment by a frame member connecting the two motors, and which unitary motor-and-tool structure may be bodily removed readily from its supporting frame and replaced therein without the necessity of alining bear ings, the motor-and-tool structure and its supporting frame cooperating toautomatically aline the four or more rotative bearings contained in the removable, unitary structure.

My invention comprises the elements and the combination and assembly thereof, all as e, 1924. Serial no. 7%,093.

shown in the accompanying drawings, as described in this specification and as particularly defined by the claims terminating the same.

In the accompanying drawings I have i1- lustrated the principles of my invention in association with a planer cutter-head for wood-finishing machines, and in a form which, while the details may be widely varied, is now preferred by me.

Figure 1 is a part section and part elevation of one end complete, and the central portion and beginning of the opposite end, showing my invention assembled in a planer.

Figure 2 is a plan view of the unitary planer cutter-head and drive structure, removed from its support.

Figure 3 is a section on ure 1.

It has been found convenient and most practical in planer cutter-heads, to provide each cutter-head with its own drive motor or motors, enabling individual controlthereof. It has also been found most desirable to provide two motors, one at each end of the cutter head shaft, for the reason that the individual motors may thus be made smaller, and the application of power is rendered more even. Such cutter heads line 3- 3 of Figtravel at a high rate of speed, generally at 3.600 revolutions per minute, although higher speeds are desirable and will be employed when suitable drive means are perfected to permit Weighing from 150 to 600 pounds, without the attached motors, it is obvious that there will be a decided tendency to vibrate if they are not firmly held. It is essential, therefore. that antifriction bearings be positioned as closely as possible to the ends of the cutter head itself.

Two motors have been employed heretofore, one at each end of such a cutter head, but these motors have never been built with more than one bearing each, so far as I am aware. The rotor of such a motor is itself heavy, and tends to bend and unbalance the shafts projecting from the cutter head, producing a whipping action when rotating, and therefore, to balance the weights of the motor rotors and the cutter-head, it has always been customary when two motors were employed to position the singlebearing at each side of the cutter-head intermediate the motor rotor and the cutter-head. As a result neither the cutter head nor the motor rotor is firmly held by the single bearing, and the tendency toward vibration and whipping is augmented to such an extent that the use of two motors at opposite ends of a cutter-head has been deemed impractical. Further, rotors, hung at the outer end of a shaft, beyond the single hearing, by slightly bending the shaft, disturbed the slight clearance (never more than a few thousandths of an inch). between the motor stator and its rotor, and caused a greater magnetic pull downward at the lowest point.

For these reasons it has been considered impractical heretofore to employ two motors, one at each end of a cutter head shaft. Two such motors could be made to synchronize sufficiently well, but because of the design of the bearings tended to cause too great vibration. It has never been considered possible to employ additional bearings for the outer ends of such shafts, for the reason that it has been deemed mechanically impossible so to aline the four bearings re: quired upon the single shaft and to hold these four bearings in proper alinen'ient as to cause them all to function properly and without cramping the shaft. My invention, therefore, is designed to enable four such bearings, two immediately adjacent the opposite ends of the cutter head itself and two at the ends of the shaft extensions outside of the motor armatures, to be exactly alined with ease. and with. certainty, and thereby to make practical the employment of two driving motors.

My invention is also designed to enable such a cutter-head shaft and its motors to be assembled as a unitary structure capable of being released and removed. with a minimum of difficulty and replaced when necessary without the necessity of again alining four bearings. In other words, it is my object to provide a construction whereby only two bearings need ever be alined with one another, and so that by thus alining two bearing surfaces the rotating unit and its four bearings will automatically be alined when placed in the machine.

The form of the cutter-head may be any that is suitable or desired. As shown herein the. head 1 contains knives 1O suitable held in place, as by the bolts 11, the head 1 havin shaft extensions 12 extendin axiall b n D thereof at opposite enos. Preferably the head 1 and the two extensions 12 are formed as a single forging. Naturally the two ex tensions 12 and the head 1 are ahned axiall J in finishing.

A motor is associated with each extension 12 the two ends beinp IQCt-lCilllV identical. Q 1 This motor may take any desired form, and as shown herein comprises a ring 2, supportlng held magnets 20, the ring being closed the weight of the motor the bearing blocks 41, the entire by end bells 21 and 22. The armature 23 is secured to rotate with the shaft extensions 12. Preferably the inner bell 22 has formed thereon or secured thereto a sleeve 2d, the outer periphery of which I prefer shall be exactly cylindrical and exactly coaxial with the remainder of the motor housing.

An antifriction bearing 3 is formed in the end of the bell 21, outward of the rotating armature 23, to support the outer end of the shaft extension 12 from the motor housing. In the inner end of the sleeve 24 and as close to the cutterheads l as is practicable, a second antifriction bearing 30 is interposed be tween the interior of the sleeve 2e and the shaft extension 12. These two bearings 3 V and 30 are so mouined in the motor housing that the two bearings for each housing are axially alined with each other and with the sleeve 24-.

Collars 25 and 26 are shown as secured at the end of the sleeve 21, cooperating with dust collars 15 and 16, respectively, to exclude dust from the bearing 30. At one end of the cutter-head 1 this bearing may he fixed in oosition between these collars 25 and 26. in order to prevent endwise movement of the cutter-head and sha ft extensions 12. At the other side of the cutter-head 1 the bearing 30 is preferably floating axially, that is, it is not strictly confined between the collars 25 and 26, but is allowed some freedom of movement axially of the shaft extension 12. Neither of the bearings 25 is strictly confined, thus endwise expansion of the shafts 12 is permitted.

By this construction the two motors and the cutter-head form a complete unit such as is shown in lifted from anysupport or placed therein. 7? 1 f for this unit is shown as comprising a yolre a connecting two bearing blacks tl which are formed of a shape to receive the sleeves 24:. Preferably these blocks 41, together with the retaining caps 4-2 which are suitably secured thereto, as by bolts 10, are cylindrical and the bearing surfaces l thereof are alined by boring them simultaneously at a single setting of the yoke in the boring mill. By this means, by scraping, or by any other suitable operation such as is common in the art of alining bearings, the surfaces 11 i may be made to exactly and accurately aline. Henceif the leeves 2 1- are received therein they will accurately'aline one with the other.

It is a simple matter to aline any pair of bearings such d 30. By forming the sleeves 24 so that they are exactly alined with the shaft extensions 12 extending therethrough and the alined bearhgs 3 and 30 7 sleeves 2t in hove, it is clear that tl' erein, and by al ng the two the manner explai .ed

by depositing the unit shownln Figure 2 in series Figure 2, and rmay thus be. 7

bearings 3, 30, 30, 3 will properly and automatically aline themselves.

The yoke at may be supported in any suitable manner, and as shown is guided on the bed frame 5 through the engagement of guides with fixed guides 51 on the bed frame. For vertical adjustment a screw 6 is suitably rotated, as through gears 60, and as it turns in a nut 61 supported from the yoke 4 or in an extension thereof, the yoke and the unit supported therein may be properly adjusted vertically relative to the working table 55.

Recognizing the desirability, and in fact the necessity, of supporting the cutter head at opposite ends and as closely as possible to its ends, it has been proposed heretofore to aline three such antifriction bearings, two forming the bearings for a motor armature at one end of a planer cutter head shaft, and the third being supported at the opposite side of the cutter head. The desirability of employing two motors, one at each end of the cntterhead, to equalize the torque and to steady the cutter, has likewise been recognized, but the construction employing only two bearings has been found impractical, due to excessive vibration, and it has been considered impracticable to aline four such bearings having a common support such as the yoke 4-, and hence the advantages of dual drive of such a shaft have been of necessity foregone because of the presumed mechanical impracticability of alining the four bearings required. \Vith my invention, once the surfaces 4 1 are properly alined, the bearings 3, 30, 30, 3 automatically aline themselves when the cutter-head unit is received in the bearing blocks ll,

Further, by reason of the bearings 3, rigidly held outside of the rotating armatures 23, it possible to increase the length of the shaft extension 12 beyond the inner bear ing 30, enabling the use of longer armatnres and field coils, and increasing the power of the motors thereby. In forms employing two bearings only it is necessary to keep these hearings as close to the cutter head as possible, and the length of the extending shaft is of necessity limited, and the power thereby kept at a minimum. Thus increasing the power of itself tends to reduce vibration and lengthens the life of the machine.

Vhat I claim as my invention is:

1. A mounting for a rotary tool comprising, in combination with a tool having coaxial shaft extensions at each end, a motor housing surrounding each of said shaft extensions, ayoke having two alined bearing boxes receiving and alining said motor housings, and a pair of spaced antifriction bearings interposed between each motor housing and the shaft extending therethrough, the antifriction bearings of each pair being alined with each other and with theaxis of their respective motor housings.

2. A mounting for a rotary tool comprising, in combination with shaft extensions at opposite ends of said tool, a housing about each of said shaft extensions, an anti-friction bearing interposed between each end of each shaft extension and its housing, and means for alining said four bearings comprising a sleeve upon each of said housings coaxial with the two bearings therein, and a supporting yoke having two coaxial sleevereceiving blocks in which said sleeves are received and alined with each other.

3. In combination with a rotary tool having shaft extensions at each end coaxial therewith, an electric motor including a motor rotor and a housing associated with each of said shaft extensions, a bearing interposed between each shaft extension and its motor housing at each side of each motor rotor, a supporting portion of each motor housing being axially alined with the two bearings therein, and a supporting yoke having two coaxial blocks, each of said motor-supporting portions being received in'its respective block to aline them with each other.

l. In combination with a rotary cutterhead, a shaft. extension extending from each end of said cutter-head and coaxial therewith, a motor including a housing associated with each shaft extension, each motor having a rotor secured upon its shaft extension towards its outer end, a sleeve projecting inward from each motor housing towards the cutter-head, and surrounding the shaft extension, a bearing interposed between the shaft extensions and that end of each sleeve which is closest the cutter-head, a bearing interposed between each motor housing and the outer end of each shaft extension, outward of the rotors, the sleeve and the two bearings for each motor being axially alined, and a Support for said two sleeves including means for maintaining them in axia alinement.

5. A driving mount for a rotary tool comprising a shaft, a tool centrally mounted thereon, a motor rotor secured upon each end of said shaft, a motor casing and stator for each rotor, said casings having bearings for theshaft at each side of the rotors of which the inner bearing is closely adjacent to the tool, and a frame connecting said rotor casings to join them together as a rigi whole.

6. A driving mount for a rotary tool comprising a shaft, a tool centrally mounted thereon, a motor rotor secured upon each end of said shaft, a motor casing and stator for each rotor, said casings having bearings for the shaft at each side of the rotors of which the inner bearing is closely adjacent to the tool, a frame connecting said rotor casings to join them together as a rigid whole, and means for securing said structure upon the machine frame by the frame which connects the motor casings.

7. A mounting for a rotary tool comprising, in combination with a tool having coaxial shaft extensions, at each end, a motor including a supporting housing surrounding each of said sh 't extensions, a yoke having two alined bearboxes receiving and alining staid motor housings, a pair of axially spaced antifriction bearings interposed be tween each motor housing and the shaft extending thcu'ethrou-gln the antifriction bearings of each pair being alined with each other and with th axis of their respective motor housings. and a cap associated with each bearing box to hold the motor housings in position therein, and removable to permit removal of the tool, shaft extensions and motors as a unit.

8. In combination with a rotary tool having shaft extensions at each end coaxial there-with, an electric motor including a motor housing associated with each of said shaft extensions, dust collars interposed between each shaft extension and its housing, two anti-friction bearings being held in position axially of the shaft extensions by said dust collars, the other three being free to move axially a limited amount, and supporting means for said two motor housings having means for alining said housings, thereby to aline said four antifriction bearings.

9. in a rotary tool of the character specified, a continuous shaft, a tool thereon be tween its ends, a motor armature upon said shaft at each side of said tool, bearings arranged in pairs at each side of the tool, the bearings of each pair being at opposite ends of the respective armatures, a motor casing enclosing each of said armatures, each casing supporting the pair of bearings associated with the corresponding armature, and said casings at opposite sides of the tool being independent of each other, and means for supporting the dual motor-and-tool unit and for automatically aligning the pairs of bearings with each other.

10. In a rotary tool of the character specitied, a continuous shaft, a tool thereon between its ends, a motor armature upon said shaft at each side of said tool, bearings g pairs at each side of the. tool, the bearings of each pair being at opposite ends of the respective armatures, a motor casing enclosing each of said armatures, each casing supporting the pair of bearings associated with the corresponding armature, and said casings at opposite sides of the tool being independent of each other, and means for supporting the dual motor-and-tool unit and for automatically aligning the pairs of bearings with each other, and means for retaining each of said housings upon its shaft end, whereby the motor-and-tool unit may be removed from and inserted within its support at will.

11. A rotary tool con'iprising a rigid integral tool and shaft extensions at each end, alined axially with said tool, a motor rotor upon, each of said shaft extensions, a motor housing surrounding each of said motor rotors, the two motor housings being connected only through said tool and its exteninms, a pair of longitudinally spaced aligned be rings interpo.:cd between each shaft extension and its associated motor housing,

arransred in and means supportingly engageable with.

both of said motor housings, thereby to support said tool and to align the four bearings through the rigid tool and its extensions.

12. A rotary tool comprising a rigid integral tool and shaft extensions at each end, aligned axially with said tool, a motor rotor upon each of said shaft extensions, a motor housing surrounding each of said motor rotors, the two motor housings being connected only through said tool and its extensions, a pair of longitudinally spaced aligned bearings interposed between each shaft extension and its associated motor housing, the inner bearing of each pair lying closely adjacent the adjoining end of the tool, and

the outer bearing of each pair lying outside its corresponding motor rotor, and a bifurcated yoke supportingly engageablesvith each of said motor housings substantially between the bearings thereof, thereby to support the tool and to align the four bearings along the axis thereof.

Signed at Seattle, King County, YVashin-gton.

ORR-A W. lVEBB. 

